Blood and hair samples, finger printing, gene, any thing available for matching.
If he doesn't have any sort, then he is already a zombie or non-existing, some one is impersonating him, might still be alive. Or he is still alive, shave his beard, wear denim jean, sunglases, ajrak on his sholders with ak 47 hidden uder his balley, heading to Karachi the biggest haven for criminals on earth to join some cult organization which is against jehadis, begin business, buy house in Defense and become elite. Again he would continue to be a zombie, the Living-Dead.:)